Klagenfurt am Wörthersee (Slovene: Celovec) is the capital of the federal state of Carinthia in Austria. With a population of over 90,000, it is the sixth-largest city in the country. The city is the bishop's seat of the Roman Catholic diocese of Gurk-Klagenfurt and home to the Alpen-Adria University.

The city of Klagenfurt is located in southern Austria, midway across the nation, near the international border. It rests in the middle region, almost as far from Innsbruck, to the west, as from Vienna, to the northeast.

Klagenfurt is elevated 446 m (1,463 ft) above sea level and covers an area of 120.11 km² (46.4 sq mi). It is on the lake Wörthersee and on the Glan River. The city is surrounded by several forest-covered hills and mountains with heights of up to 1,000 m (3,300 ft), for example, Ulrichsberg. To the south is the Karawanken mountain range, which separates Carinthia from Slovenia and Italy.

Klagenfurt is divided into 16 districts:

It is further divided into 25 Katastralgemeinden. They are: Klagenfurt, Blasendorf, Ehrenthal, Goritschitzen, Großbuch, Großponfeld, Gurlitsch I, Hallegg, Hörtendorf, Kleinbuch, Lendorf, Marolla, Nagra, Neudorf, St. Martin bei Klagenfurt, St. Peter am Karlsberg, St. Peter bei Ebenthal, Sankt Peter am Bichl, St. Ruprecht bei Klagenfurt, Stein, Tentschach, Viktring, Waidmannsdorf, Waltendorf, and Welzenegg.